Add forloop to render for syntax

lib/liquid/tags/render.rb

@@ -43,19 +43,26 @@ module Liquid
 
       context_variable_name = @alias_name || template_name.split('/').last
 
-      render_partial_func = ->(var) {
+      render_partial_func = ->(var, forloop) {
         inner_context = context.new_isolated_subcontext
         inner_context.template_name = template_name
         inner_context.partial = true
+        inner_context['forloop'] = forloop if forloop
         @attributes.each do |key, value|
           inner_context[key] = context.evaluate(value)
         end
         inner_context[context_variable_name] = var unless var.nil?
         partial.render_to_output_buffer(inner_context, output)
+        forloop&.send(:increment!) if forloop
       }
 
       variable = @variable_name_expr ? context.evaluate(@variable_name_expr) : nil
-      variable.is_a?(Array) ? variable.each(&render_partial_func) : render_partial_func.call(variable)
+      if variable.is_a?(Array)
+        forloop = Liquid::ForloopDrop.new(template_name, variable.count, nil)
+        variable.each { |var| render_partial_func.call(var, forloop) }
+      else
+        render_partial_func.call(variable, nil)
+      end
 
       output
     end